USB connectors have been widely used in electronic devices such as power adapters, mobile power sources, notebook computers, mobile phones, and tablet computers. The USB connectors may be used for charging and data transmission functions. Operation of USB connectors is standardized through a USB standard.
A recently released USB Type-C cable and connector specification defines a new Type-C USB connector that meets the USB 3-1 protocol of the USB specification. The Type-C USB connector has a higher data rate, a higher configurable charging current, and supports bidirectional insertion of a USB plug into a USB socket as compared to the previous Type-B USB connector.
When a Type-C USB connector and a corresponding cable is used to connect an upstream facing port (UFP) of an electronic device to a downstream facing port (DFP) of another electronic device, the DFP device may output a voltage to the UFP device through a pin of the USB connector. After removal of the cable, the VBUS pin of the connector should be discharged. At present, related protocols of the Type-C USB specify various principles (including power consumption, discharge time, slew rate (SR), and the like) that should be followed in the process of discharging the voltage of the VBUS pin. However, no effective solution of controlling the process of discharging the voltage of the VBUS pin according to specifications of the related protocols of the Type-C USB has been found yet.
The information disclosed above in the Background is merely intended to facilitate the understanding of the background of the present subject matter. Therefore, it may contain information beyond what those of ordinary skills in the art might have known about the prior art.